1. Field of the Invention
This invention relates to a friction pad for a disc brake to be used in a braking system of vehicles, such as automobiles, for example.
2. Prior Art
A disc brake usually includes a shim disposed between a pawl portion in a caliper and a pad and between a piston in the caliper and a pad, for the purpose of restricting noise in such a disc brake. The shim comprises a sheet attached to a back plate for the pads.
The shim is formed by blanking a continuous length of a web member. In order to facilitate feeding or advancement of the web member during manufacture of the shim, the web member is formed with pilot holes to accommodate feed pawls therein. Conventionally, such pilot holes are formed in the area of the web member from which the shim is formed. As will be explained in detail below, a viscous fluid substance, such as grease, may be interposed between the shim and a friction pad on which the shim is mounted, for the purpose of restricting noise in the disc brake. In such a case, a problem has been experienced in that the fluid leaks or flows through such pilot holes, when the pilot holes in the shim are disposed at or adjacent to the viscous fluid.
In order to avoid the above problem, the pilot holes are conventionally formed in a portion outside the area of the web corresponding to the shim, so that such portion including the pilot holes may be subsequently removed from the shim. It is noted, however, that such work disadvantageously requires an increased number of fabrication stages, as well as increased unnecessary or waste material.